DHCP Server ----------- Multiple DHCP Servers can be run from a single machine. Each DHCP service is identified by a `shared-network-name`. DHCP Server Example ^^^^^^^^^^^^^^^^^^^ In this example, we are offering address space in the 172.16.17.0/24 network, which is on eth1, and pppoe0 is our connection to the internet. We are using the network name `dhcpexample`. Prerequisites ^^^^^^^^^^^^^ Configuring the PPPoE interface is assumed to be done already, and appears on `pppoe0` Interface Configuration ^^^^^^^^^^^^^^^^^^^^^^^ .. code-block:: none set interface ethernet eth1 address 172.16.17.1/24 Multiple ranges can be defined and can contain holes. .. code-block:: none set service dhcp-server shared-network-name dhcpexample authoritative set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 default-router 172.16.17.1 set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 dns-server 172.16.17.1 set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 lease 86400 set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 range 0 start 172.16.17.100 set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 range 0 stop 172.16.17.199 Explanation ^^^^^^^^^^^ * :code:`set service dhcp-server shared-network-name dhcpexample authoritative` This says that this device is the only DHCP server for this network. If other devices are trying to offer DHCP leases, this machine will send 'DHCPNAK' to any device trying to request an IP address that is not valid for this network. * :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 default-router 172.16.17.1` This is a configuration parameter for the subnet, saying that as part of the response, tell the client that I am the default router for this network * :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 dns-server 172.16.17.1` This is a configuration parameter for the subnet, saying that as part of the response, tell the client that I am the DNS server for this network. If you do not want to run a DNS server, you could also provide one of the public DNS servers, such as google's. You can add multiple entries by repeating the line. * :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 lease 86400` Assign the IP address to this machine for 24 hours. It is unlikely you'd need to shorten this period, unless you are running a network with lots of devices appearing and disappearing. * :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 range 0 start 172.16.17.100` Make a range of addresses available for clients starting from .100 [...] * :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 range 0 stop 172.16.17.199` [...] and ending at .199 Failover ^^^^^^^^ VyOS provides support for DHCP failover: .. code-block:: none set service dhcp-server shared-network-name 'LAN' subnet '192.168.0.0/24' failover local-address '192.168.0.1' set service dhcp-server shared-network-name 'LAN' subnet '192.168.0.0/24' failover name 'foo' set service dhcp-server shared-network-name 'LAN' subnet '192.168.0.0/24' failover peer-address '192.168.0.2' .. note:: `name` must be identical on both sides! The primary and secondary statements determines whether the server is primary or secondary .. code-block:: none set service dhcp-server shared-network-name 'LAN' subnet '192.168.0.0/24' failover status 'primary' or .. code-block:: none set service dhcp-server shared-network-name 'LAN' subnet '192.168.0.0/24' failover status 'secondary' .. note:: In order for the primary and the secondary DHCP server to keep their lease tables in sync, they must be able to reach each other on TCP port 647. If you have firewall rules in effect, adjust them accordingly. Static mappings MAC/IP ^^^^^^^^^^^^^^^^^^^^^^ .. code-block:: none set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 static-mapping static-mapping-01 ip-address 172.16.17.10 set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 static-mapping static-mapping-01 mac-address ff:ff:ff:ff:ff:ff DHCP server options ^^^^^^^^^^^^^^^^^^^^^^^^^ default-router (DHCP option 003) :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 default-router ` dns-server (DHCP option 006) :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 dns-server ` domain-name Client domain name (DHCP option 015) :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 domain-name ""` domain-search (DHCP option 119) This option can be given multiple times if you need multiple search domains :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 domain-search ""` :code:`set service dhcp-server shared-network-name dhcpexample subnet 172.16.17.0/24 domain-search ""` DHCPv6 server ------------- VyOS provides DHCPv6 server functionality which is described in this section. In order to use the DHCPv6 server it has to be enabled first: .. code-block:: none set service dhcpv6-server To restart the DHCPv6 server (operational mode): .. code-block:: none restart dhcpv6 server To show the current status of the DHCPv6 server use: .. code-block:: none show dhcpv6 server status Show statuses of all assigned leases: .. code-block:: none show dhcpv6 server leases DHCPv6 server options ^^^^^^^^^^^^^^^^^^^^^ DHCPv6 server preference value ****************************** Clients receiving advertise messages from multiple servers choose the server with the highest preference value. The range for this value is `0...255`. Set a preference value for the DHCPv6 server: .. code-block:: none set service dhcpv6-server preference Delete a preference: .. code-block:: none set service dhcpv6-server preference Show current preference: .. code-block:: none show service dhcpv6-server preference Specify address lease time ************************** The default lease time for DHCPv6 leases is 24 hours. This can be changed by supplying a `default-time`, `maximum-time` and `minimum-time` (all values in seconds): .. code-block:: none set service dhcpv6-server shared-network-name subnet lease-time {default | maximum | minimum } Reset the custom lease times: .. code-block:: none delete service dhcpv6-server shared-network-name subnet lease-time {default | maximum | minimum} Show the current configuration: .. code-block:: none show service dhcpv6-server shared-network-name subnet lease-time {default | maximum | minimum} Specify NIS domain ****************** A Network Information (NIS) domain can be set to be used for DHCPv6 clients: .. code-block:: none set service dhcpv6-server shared-network-name subnet nis-domain To Delete the NIS domain: .. code-block:: none delete service dhcpv6-server shared-network-name subnet nis-domain Show a configured NIS domain: .. code-block:: none show service dhcpv6-server shared-network-name subnet nis-domain Specify NIS+ domain ******************* The procedure to specify a Network Information Service Plus (NIS+) domain is similar to the NIS domain one: .. code-block:: none set service dhcpv6-server shared-network-name subnet nisplus-domain To Delete the NIS+ domain: .. code-block:: none delete service dhcpv6-server shared-network-name subnet nisplus-domain Show a configured NIS domain: # show service dhcpv6-server shared-network-name subnet nisplus-domain Specify NIS server address ************************** To specify a NIS server address for DHCPv6 clients: .. code-block:: none set service dhcpv6-server shared-network-name subnet nis-server Delete a specified NIS server address: .. code-block:: none delete service dhcpv6-server shared-network-name subnet nis-server Show specified NIS server addresses: .. code-block:: none show service dhcpv6-server shared-network-name subnet nis-server Specify NIS+ server address *************************** To specify a NIS+ server address for DHCPv6 clients: .. code-block:: none set service dhcpv6-server shared-network-name subnet nisplus-server Delete a specified NIS+ server address: .. code-block:: none delete service dhcpv6-server shared-network-name subnet nisplus-server Show specified NIS+ server addresses: .. code-block:: none show service dhcpv6-server shared-network-name subnet nisplus-server Specify a SIP server address for DHCPv6 clients *********************************************** By IPv6 address ############### A Session Initiation Protocol (SIP) server address can be specified for DHCPv6 clients: .. code-block:: none set service dhcpv6-server shared-network-name subnet sip-server-address Delete a specified SIP server address: .. code-block:: none delete service dhcpv6-server shared-network-name subnet sip-server-address Show specified SIP server addresses: .. code-block:: none show service dhcpv6-server shared-network-name subnet sip-server-address By FQDN ####### A name for SIP server can be specified: .. code-block:: none set service dhcpv6-server shared-network-name subnet sip-server-name Delete a specified SIP server name: .. code-block:: none delete service dhcpv6-server shared-network-name subnet sip-server-name Show specified SIP server names: .. code-block:: none show service dhcpv6-server shared-network-name subnet sip-server-name Simple Network Time Protocol (SNTP) server address for DHCPv6 clients ********************************************************************* A SNTP server address can be specified for DHCPv6 clients: .. code-block:: none set service dhcpv6-server shared-network-name subnet sntp-server-address Delete a specified SNTP server address: .. code-block:: none delete service dhcpv6-server shared-network-name subnet sntp-server-address Show specified SNTP server addresses: .. code-block:: none show service dhcpv6-server shared-network-name subnet sntp-server-address DHCPv6 address pools ^^^^^^^^^^^^^^^^^^^^ DHCPv6 address pools must be configured for the system to act as a DHCPv6 server. The following example describes a common scenario. Example 1: DHCPv6 address pool ****************************** A shared network named `NET1` serves subnet `2001:db8:100::/64` which is connected to `eth1`, a DNS server at `2001:db8:111::111` is used for name services. The range of the address pool shall be `::100` through `::199`. The lease time will be left at the default value which is 24 hours. .. code-block:: none set service dhcpv6-server shared-network-name NET1 subnet 2001:db8:100::/64 address-range start 2001:db8:100::100 stop 2001:db8:100::199 set service dhcpv6-server shared-network-name NET1 subnet 2001:db8:100::/64 name-server 2001:db8:111::111 Commit the changes and show the configuration: .. code-block:: none commit show service dhcpv6-server shared-network-name NET1 { subnet 2001:db8:100::/64 { address-range { start 2001:db8:100::100 { stop 2001:db8:100::199 } } name-server 2001:db8:111::111 } } Static mappings ^^^^^^^^^^^^^^^ In order to map specific IPv6 addresses to specific hosts static mappings can be created. The following example explains the process. Example 1: Static IPv6 MAC-based mapping **************************************** IPv6 address `2001:db8:100::101` shall be statically mapped to a device with MAC address `00:15:c5:b7:5e:23`, this host-specific mapping shall be named `client1`. .. note:: The MAC address identifier is defined by the last 4 byte of the MAC address. .. code-block:: none set service dhcpv6-server shared-network-name NET1 subnet 2001:db8:100::/64 static-mapping client1 ipv6-address 2001:db8:100::101 set service dhcpv6-server shared-network-name NET1 subnet 2001:db8:100::/64 static-mapping client1 identifier c5b75e23 Commit the changes and show the configuration: .. code-block:: none show service dhcp-server shared-network-name NET1 shared-network-name NET1 { subnet 2001:db8:100::/64 { name-server 2001:db8:111::111 address-range { start 2001:db8:100::100 { stop 2001:db8:100::199 { } } static-mapping client1 { ipv6-address 2001:db8:100::101 identifier c5b75e23 } } }